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					UNIT E - Preventative Maintenance



                                                             UNIT E -
                                                    PREVENTATIVE MAINTENANCE

INTRODUCTION  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-2

PRE-TRIP INSPECTION  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-3
   VEHICLE OVERVIEW  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-4.
       Engine Compartment Inspection  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-5.
       Inspect the Inside of Bus  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-7
       Driver Compartment  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-7
       Passenger Entry  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-12
       Passenger Compartment  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-12
   Inspect Outside of Bus: Walk-Around Inspection  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-13
       Tires, Wheels, and Rims .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-13
       Check Right Front .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-14.
       Check Front Side  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-15.
       Check Left Front  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-16
       Check Left Side  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-16
       Check Left Rear  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-16
       Check Rear Side  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-17
       Check Right Rear  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-17
       Check Brake System  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-17
       Automatic Brake Adjusters (ASAs)  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-18

PREVENTIVE MAINTENANCE WHILE ON THE ROAD  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-19
   Detecting Abnormal Vehicle Behavior  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-19
      Continuous Checks  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-19
      Check Parking Brake  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-19
      Check Service Brakes  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-20
      Check Transmission  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-20
      Check Steering  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-20
      Check Suspension  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-20
      Check Engine  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-20
      Check Your Tires  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-20
   Good Driving Habits  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-21
      Starting the Bus and Basic Operations .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-21
      Proper Use of the Clutch  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-21
      Proper Use of the Brakes  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-22
      Protection of the Rear Axle  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-22
      Proper Use of the Transmission  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-22

POST-TRIP PREVENTIVE MAINTENANCE PROCEDURES  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-23
   Importance of Reporting Problems  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-24.
   Five Basic Items Mechanics Want You to Know  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  .  . E-24.




Pennsylvania School Bus Driver’s Manual • PUB 117                                                                                                                                                                             E-1
                                                                               UNIT E - Preventative Maintenance



                                    UNIT E -
                           PREVENTATIVE MAINTENANCE

                                         INTRODUCTION
The life of a school bus and the dependable service it can provide to you as an operator as well as to the pupils
you are transporting is directly related to how you care for your bus. Central to this is a planned, budgeted and
proactive preventative maintenance system. This system involves such items as service, adjustments,
replacements, inspections based on pre-determined intervals, and tolerances. These minimize failures and
costs, and maximize safe and comfortable operations. Most significantly, safety is the most important and
obvious reason for performing inspections: inspecting your vehicle helps you to know your vehicle is safe. You
should never operate a vehicle that is not running properly, is not safe or does not have the proper equipment
on board.

As a school bus operator, you have significant responsibility in the preventive maintenance program, especially
in the proactive component of preventive maintenance. Remember: with an effective preventive maintenance
system, service begins with the pre-trip inspection. With an ineffective preventive maintenance system,
breakdowns and complaints control the service. From an operator’s standpoint, preventive maintenance
includes the following items:

      1. Pre-trip inspection;
      2. Operational inspection; and
      3. Post-trip inspection.



As indicated in this unit, as an operator, you should NOT be making repairs yourself; this is the role of your
maintenance team. Report, don’t diagnose. However, since you are on the road with your vehicle for several
hours each day, you are in the best position to observe how it performs under all conditions. Learn to recognize
defects both during the pre-trip inspection and while on the road, and immediately report problems to your
supervisor or the bus maintenance department. Problems cannot be repaired, if they are not reported.

This unit covers each of these items as part of your normal daily preventive maintenance tasks. Responsibility
for these tasks may vary due to differences in buses and/or local policy. If you are ever unsure of the preventive
maintenance duties assigned to you, ask your supervisor.




E-2                                                           Pennsylvania School Bus Driver’s Manual • PUB 117
UNIT E - Preventative Maintenance



                                    PRE-TRIP INSPECTION
The purpose of a pre-trip inspection is to identify problems that could cause a crash or breakdown. Each
school bus operator may have unique methods or procedures for completing and documenting a pre-trip
inspection, so work with your supervisor to review system-specific policies and/or checklists. The key for you,
the operator, is to complete your pre-trip inspection the same way each time. In this fashion, you will learn all
the correct steps, improve the efficiency of your inspection and will be less likely to forget something important.

The following is a pre-trip inspection that should take an operator about 15. minutes to complete. This is only a
recommended procedure that makes logical sequential sense. If you have a more efficient process that still
covers the requirements in 4.9 CFR Section 396.13 (Driver Inspection), or if your school district or contractor
requires something different, use their procedures. Remember, federal regulations require you to ALWAYS be
satisfied your bus is in good operating condition and you review the last driver inspection report.

It is also good practice to always complete your pre-trip inspection the same way each time so you will be less
likely to forget a step. A few items to have on hand when you complete your pre-trip inspection include:

   • Work gloves to keep your hands clean;
   • Rags for removing caps and checking fluid levels under the hood;
   • Paper towels for cleaning small spills;
   • Window cleaning fluid for washing windows, mirrors and headlights. It is good practice to clean all lights,
     reflectors and glass, as you go along; and
   • A checklist provided by your employer (may be company-specific) for making sure you check all important
     items.


Remember federal regulations require that before driving your bus, you shall:
    1. Be satisfied it is in safe operating condition;
    2. Review the last driver vehicle inspection report; and
    3. Sign the report, only if defects or deficiencies were noted by the driver who prepared the report, to
       acknowledge the driver has reviewed it and there is a certification the required repairs have been
       performed. The signature requirement does not apply to listed defects on a towed unit, which is no
       longer part of the vehicle combination.


There are also specific federal requirements for post-trip inspection in 4.9 CFR Section 396.11 (Driver Vehicle
Inspection Reports) as discussed later in this unit.




Pennsylvania School Bus Driver’s Manual • PUB 117                                                              E-3
                                                                                UNIT E - Preventative Maintenance



1.      VEHICLE OVERVIEW
As you approach the vehicle, note its general condition, and look for damage or whether the vehicle is leaning
to one side. Look under the vehicle for fluid, which may be fresh indicating oil coolant, grease, or fuel leaks. If
any of these are noted, contact your supervisor or maintenance professional. Recognize what items are critical
to operating a bus safely. If the fluid is condensation from the air conditioner, there is no need to report a
problem, but if it is a fuel leak, the bus should be immediately removed from service until the problem is
repaired. Also, check the area around the vehicle — above and below — for hazards to vehicle movement
(people, other vehicles, objects, low hanging wires or limbs, etc.). This is of particular importance for homeland
security issues.

If your vehicle has recently been in for service, pay particular attention to the problem areas to determine
whether they have been adequately repaired. Review the bus repair report and/or last bus inspection report.
This is particularly important if you are driving a bus that is not your own.

                                        Figure E-1. Pre-Trip Inspection




E-4.                                                          Pennsylvania School Bus Driver’s Manual • PUB 117
UNIT E - Preventative Maintenance



2.      ENGINE COMPARTMENT INSPECTION
Some contractors and school districts do not require drivers to perform under-the-hood checks, but all drivers
should be trained in the proper procedure. Make your first set of checks under the hood while the engine is cool
and the various fluid systems have had time to stabilize.

Ensure the parking brakes are on and/or wheels chocked. You may have to raise the hood, secure loose items
so they don’t fall and break something, or open the engine compartment door.

Check the following while the engine is not running:

  • Engine oil level – Remove the oil dipstick, wipe the dipstick clean with a rag and look at the indicator at
    the bottom of the dipstick. Push the dipstick back into the hole, making sure to push it all the way back in
    until it seats. Pull out the dipstick again and see where the oil has left a residue in relationship to the
    indicators. Make sure the level is between the ‘add’ and the ‘full’ line.
  • Coolant level in radiator – While the engine may not be running, you may be doing this check after
    someone else has used your bus, and it has not completely cooled yet. Because of this, never remove the
    radiator cap when the engine is hot. The fluid is under pressure, and you can be burned seriously.
     v Indentify the full hot and full cold level markings on the opaque white plastic coolant overflow tank
       located right next to the radiator. If the engine is hot, fill to the hot line. If the engine is cold, fill to the
       cold line. If you’re low, top it off with a 5.0/5.0 mixture of coolant and water. There is more than one type
       of coolant. Only use the type of coolant specified by the mechanic. To add the coolant, unscrew or pop
       the top of the opaque plastic reservoir, and add your mixture until it reaches the full mark. Replace the
       cap tightly. If you spill any coolant on the ground, wipe it up. Certain coolants are deadly to animals, but
       they like to drink it because it tastes sweet. If there is no fluid in the reservoir, notify the mechanic for
       instructions before starting the bus.
  • Condition of hoses –
     v To check the condition of the hoses, when the engine is cold, squeeze each hose. If the hose feels
       crunchy or brittle, it’s old and needs to be replaced.
     v Visually inspect the hoses for cracks, tears, frayed ends, and damp or wet areas. Check the clamps at
       ends of the hoses.
  • Power steering fluid level. Make sure it is above the “fill” mark –
     v Wipe the power steering fluid reservoir cap with a clean rag or paper towel before opening.
     v Visually inspect the hose for cracks, tears, frayed ends, and damp or wet areas (if any).
     v Some tanks require this to be checked when hot. Refer to your bus manual for specific details.
  • Windshield washer fluid level –
     v The windshield washer fluid reservoir is a large, clear plastic container that may be labeled with words
       or a symbol on the cap showing two sprits of water.
     v Check the fluid level. You can fill this reservoir all the way to the top.
  • Battery fluid level, connections and tie downs (battery may be located elsewhere) –
     v No smoking and extinguish all open flames. Batteries produce hydrogen gas when charging. Hydrogen
       is extremely flammable and explosive.
     v Clean the top surface to remove any dirt and debris with a rag before removing the caps.
     v Remove the vent caps by prying them up or turning them counter clockwise and look inside each cell.
       The fluid level should be level with the filler ring for each cell.
     v Use a battery fill jug. Fill any low cells with distilled water up to the proper level.



Pennsylvania School Bus Driver’s Manual • PUB 117                                                                    E-5.
                                                                                   UNIT E - Preventative Maintenance



      v Replace the vent caps and clean up any spills.
      v Warning – battery fluid is sulfuric acid. Do not get any on your skin or clothing. If battery fluid does
        make contact with your skin, flush with fresh water immediately.
      v Only use distilled water in your battery. Anything else will cause the battery to fail.
  • Automatic transmission fluid level (may require engine to be running and be fully warmed up) –
      v Be careful around the running engine. The fan might come on suddenly and catch any lose clothing or
        jewelry and may cause serious injury.
      v Pull out the dipstick and wipe it clean with a rag.
      v Put the dipstick back in the hole. Make sure to push it all the way back in until it seats.
      v Pull out the dipstick and ensure the fluid level is between the full and low levels.
      v Use a long, thin funnel to add transmission fluid through the dipstick hole if required.
      v There is more than one type of transmission fluid. Only use the type of transmission fluid specified by
        the mechanic or as shown on the dipstick or engine manual.
  • Tightness and excessive wear on belts on the alternator, water pump, and air compressor –
      v Learn how much “give” the belts should have when adjusted right, and check each one. Press lightly
      with your thumb on each belt at the belt’s longest part between pulleys. In general, there should be no
      more than ½” to 1” of movement. The belt should not be cracked. As mentioned earlier, this portion of your
      pretrip will normally be done when the engine is cool. If for some reason it is not, let the engine cool before
      checking belts, and be careful around hot engine parts and sharp edges.
  • Inspect for leaks in the engine compartment (fuel, coolant, oil, power steering fluid, hydraulic fluid,
    brake fluid, windshield washer fluid, gear oil, automatic transmission fluid, battery fluid).
      v Except for windshield washer fluid and fuel, the fluids in your bus shouldn’t get used up or go
        anywhere.
      v As brake linings wear, brake fluids will drop slightly.
      v If you notice any other fluids are low, you probably have a leak.
      v Inspect underneath the bus looking for wet areas or drips clinging to the underside of the bus.
      v Sticky sweet smelling fluid is coolant. The old color for coolant was green, now it comes in yellow, as
        well as other colors. Dark slick greasy fluid is engine oil. Honey or dark colored thick fluid with a
        chestnut smell is gear oil. Clear slippery fluid is brake fluid. Slippery red fluid is transmission fluid or
        power steering fluid. Fuel is easily identified by its odor. Windshield washer fluid comes in several
        colors – blue and orange are typical. Battery fluid could be on top of the battery. Don’t touch this.
        It is acid.
  	 v If you are running the air conditioner expect to see water dripping, which is just condensation and is
      nothing to worry about.
  	 v Look for cracked worn insulation around electrical wiring. Look for bare wire spots where the insulation
      has broken, burnt or worn away.
  	 v Don’t tug on the wires. You might pull them out of the connections and disconnect the wire.


When the engine compartment inspection is complete, carefully lower and secure hood latches or the engine
compartment door.




E-6                                                               Pennsylvania School Bus Driver’s Manual • PUB 117
UNIT E - Preventative Maintenance



3.      INSPECT INSIDE OF BUS
Once the engine compartment has been checked, inspect the inside of the bus. This task can be separated
into three areas: the driver compartment, the passenger entry and the passenger compartment. It is
recommended you start the vehicle engine and complete this portion with the engine turned on. For diesel
engines, make sure the injector pump is engaged before starting.

Refer to Unit F for starting and driving a diesel vehicle. At a minimum:
  • Make sure parking brake is on;
  • Put gearshift in neutral (or park, if available);
  • Turn off the heaters before starting, so the engine will reach operating temperature more quickly; and
  • Start the engine and listen for unusual noises.



Driver Compartment
At the start of your in-bus check, activate the four-way flashers and amber lights from the operator’s seat. From
the seated position, you can see in your mirrors whether the front ambers are working and can see the turn
signals both flashing. Later, when you walk through the bus and open the back door, you can see whether the
back turn signals are flashing and the amber lights in the back are flashing.

1) Inspect the Gauges. Check all of the following gauges:
   • Oil pressure should come up to normal within seconds after engine is started. If it does not, shut down the
     engine and notify the mechanic.
  • Ammeter and/or voltmeter should be in normal range(s).
  • Coolant temperature should begin gradual rise to normal operating range.
  • Oil, coolant and charging circuit warning lights should go out right away.
  • Fuel gauge should indicate a safe margin for the day’s trip.
  • Buses equipped with hydraulic brakes with vacuum assist have a vacuum gauge and low vacuum warning
    light. If the gauge reads less than normal or the warning light starts to blink, report the condition.
  • Air gauges with warning buzzers on buses with air brakes stop buzzing when air pressure increases
    above 60 psi. Do not drive the bus, if the pressure is less than 60 psi.



2) Check Controls. Check all of the following for looseness, sticking, damage, or improper setting:
   • Steering wheel;
  • Clutch;
  • Accelerator (gas pedal);
  • Brake Controls; and
     v Foot brake,
  	 v Parking brake,
  	 v Retarder controls (if vehicle has them),
  	 v Transmission controls.
  • Horn: Horn should be heard approximately 200’ away.




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                                                                                UNIT E - Preventative Maintenance



  • Windshield wiper/washer. Spray the washer fluid before turning on the wipers, to avoid damaging the
    windshield.
  • Lights.
      v Headlights;
      v Dimmer switch;
      v Turn signal;
      v Four-way flashers;
      v Clearance, identification, marker light switch(es);
      v School bus eight-way light system; and
      v Strobe light, if applicable.



3) Check All Mirrors. Mirrors play a critical role in the safe operation of your vehicle because they allow an
operator to observe the zone around the bus and look for students, traffic and other objects in this area (Refer
to Unit B). For example, children standing in front of the bus may not be visible in any other way. Therefore, all
mirrors must be secure, clean and unbroken. Check mirrors to make sure they are clean and adjusted so you
can see all areas around the bus from the driver’s seat and you can obtain the maximum viewing area
consistent with the vision requirements of Federal Motor Vehicle Safety Standard No. 111, “Rearview Mirrors.”
Refer to 4.9 CFR 5.71.111. See Figure E-2 below. The interior rearview mirror must provide a good view of
passengers and the area directly behind the bus. The right and left side mirrors must provide a clear view past
the right and left rear of the bus. The right and left front fender-mounted rear mirrors (convex mirrors) must
provide a clear view from the forward-most point of the front fenders past the rear of the bus. The left front
fender-mounted crossover mirror (convex) must provide a view of the blind area directly in front of the bus.

                   Figure E-2. Location of Test Cylinders for School Bus Field-of-View Test
                                        All Dimensions in Meters (m)/




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UNIT E - Preventative Maintenance



Outside Left and Right Side Flat Mirrors.
These mirrors are mounted at the left and right front corners of the bus at the side or front of the windshield.
They are used to monitor traffic, check clearances and students on the sides and to the rear of the bus. There
is a blind spot immediately below and in front of each mirror and directly in back of the rear bumper. The blind
spot behind the bus could extend up to 4.00 feet depending on the width of the bus. Ensure the mirrors are
properly adjusted so you can see:

  • 200 feet or four bus lengths behind the bus;
  • Along the sides of the bus; and
  • The rear tires touching the ground.



                                 Figure E-3. Left and Right Side Flat Mirrors




               May use in conjunction with the left and right side
                convex mirrors to obtain the desired visibility.




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                                                                              UNIT E - Preventative Maintenance



Outside Left and Right Side Convex Mirrors.
The convex mirrors are located below the outside flat mirrors. They are used to monitor the left and right sides
at a wide angle. They provide a view of traffic, clearances and students at the side of the bus. These mirrors
present a view of people and objects that does not accurately reflect their size and distance from the bus.
Ensure the mirrors are properly adjusted so you can see:

  • The entire side of the bus up to the mirror mounts;
  • Front of the rear tires touching the ground; and
  • At least one traffic lane on either side of the bus.



                               Figure E-4. Left and Right Side Convex Mirrors




              May use in conjunction with the left and right side
             standard (flat) mirrors to obtain the desired visibility.




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UNIT E - Preventative Maintenance



Outside Left and Right Side Cross View Mirrors.
These mirrors are mounted on the left and right front corners of the bus. They are used to see the “danger
zone” area directly in front of the bus not visible by direct vision, and to view the “danger zone” areas to the left
side and right side of the bus, including the service door and front wheel areas. The mirror presents a view of
people and objects that does not accurately reflect their size and distance from the bus. The driver must ensure
these mirrors are properly adjusted. Ensure the mirrors are properly adjusted so you can see:

  • The entire area in front of the bus from the front bumper at ground level to a point where direct vision is
    possible. Direct vision and mirror view vision should overlap;
  • The right and left front tires touching the ground; and
  • The area from the front of the bus to the service door.
These mirrors, along with the convex and flat mirrors, should be viewed in a logical sequence to ensure a child
or object is not in any area of the danger zone.

                                  Figure E-5. Left and Right Cross View Mirrors

         LEFT CROSS VIEW MIRROR RIGHT CROSS VIEW MIRROR




Overhead Inside Rearview Mirror.
This mirror is mounted directly above the windshield on the driver’s side area of the bus. This mirror is used to
monitor passenger activity inside the bus. It may provide limited visibility directly in back of the bus, if the bus is
equipped with a glass-bottomed rear emergency door. There is a blind spot area directly behind the driver’s
seat as well as a large blind spot area beginning at the rear bumper and could extend up to 4.00 feet or more
behind the bus. You must use the exterior side mirrors to monitor approaching traffic and enter this area.
Ensure the mirrors are properly adjusted so you can see:

  • The top of the rear window in the top of the mirror; and
  • All of the students, including the heads of the students right behind you.



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                                                                                 UNIT E - Preventative Maintenance



Passenger Entry

    1) Check Service Doors – Open and close your service door to ensure it operates smoothly, and there
       is no broken or obscure glass.
    2) Check the Stairwell – Ensure the skid resistant tread is in good operating condition and the stairs
       themselves are not bent or rusting. Some stairwells are lighted. If this is the case, the lens cover
       should not be broken. Make sure if a light is present, it operates correctly.
    3) Check the Handrail – This item is required in a school bus, and it should be secure and undamaged.
       This is of particular importance so it does not snag a student’s clothing and drag them, if the bus is in
       motion.



Passenger Compartment
A walk-through examination of the passenger compartment should be completed next. You should examine
seats to ensure they are secure to the floor with no broken parts, and the condition of the upholstery is
adequate. This includes making sure the seat bottoms are secure on the way down the aisle and also check for
vandalism. Correct any problems, if possible, and report any hazardous conditions to your supervisor. Also be
sure the compartment is free of clutter or trash, which could cause a student to slip or fall.

At the end of the walk-through, be sure the emergency door(s) is unlocked and opens and closes properly, and
the warning buzzer works properly. While the door(s) must be shut to prevent carbon monoxide fumes from
entering, it must not be locked at any time during operation of the bus. In addition, the door and aisle should
never be blocked. The rear emergency door and side emergency door exits must open and close properly from
outside the bus.

When you walk through the bus and open the back door, you can see that the back turn signals are flashing,
and the amber lights in the back are flashing.

Check emergency exit windows on sides and emergency escape hatches in the roof to see they are
operational and the warning buzzer works properly.

Lastly, check the school bus emergency equipment. This includes:

  • Spare electrical fuses, unless vehicle has circuit breakers;
  • Three red reflective triangles;
  • Properly charged and rated fire extinguisher. This is a fire extinguisher with a total rating of not less than
    two A-10 BC for electrical and liquid-fuel fires. Ensure the pin is in place. You need to make sure the fire
    extinguisher is inspected at least once a year to ensure it is fully charged, properly filled and operable.
    Upon approval, the fire extinguisher shall be tagged, signed and dated. Check to make sure your
    extinguisher is tagged, signed and dated as part of your inspection. Refer to Section 171.5.1, 171.122,
    171.132, and 171.14.7 of Title 67 for additional details on fire extinguishers;
  • Complete First Aid Kit (refer to Unit I) including a Body Fluid Clean-Up Kit;
  • Pry bar;
  • Tire chains (Optional: where winter conditions require them);
  • Tire changing equipment (optional);
  • List of emergency phone numbers; and
  • Crash reporting packet (Refer to Unit I).




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UNIT E - Preventative Maintenance



Refer to state regulations in Title 67, Chapter 171 for additional regulatory information regarding safety
equipment: www.pacode.com.

Don’t forget to check the interior signal pilot and dashboard lights. Make sure the headlight dimmer switch is
working, and check the dome and stepwell lights. Lastly, activate the school bus eight-way light system. While
it is on, the red flashing lights will be activated once you open the service door of the bus. Leave all lights on at
this point so you can check them from the outside during your walk-around inspection.



4.      INSPECT OUTSIDE OF BUS: WALK-AROUND INSPECTION
Walk around the bus for the next set of checks. Leave the engine running with the parking brake set,
transmission out of gear, and lights and signal devices left on. To save time, it is a good idea to team up with
another driver when checking mirrors, headlights, the red and amber flashing lights of the school bus eight-way
light system, side marker lights, brake lights, and back-up lights.



Tires, Wheels, and Rims
Tires, wheels and rims operate together. Tires should be of the same size, evenly matched, and of the same
type (radial or bias type). The recaps are permitted on rear tires unless they are single wheels, but not on the
front. If using recapped tires, they must be stamped as “regroovable.” Refer to Section 171.36 of Title 67 for
additional details. The tread should not be separating from the tire. Rims should not be bent or damaged, and
should have no welding repairs. Look for rust trails, which may indicate the rim is loose on the wheel. Rust
around lug nuts may also indicate looseness. You may need to tighten with a wrench. Also, the hub oil seals,
axle seals, and wheel bearing seals should not be leaking. Look for any other signs of misalignment or missing
lug nuts.

When walking around, carry your pry bar or tire buddy, and strike each tire; the bar should bounce back
adequately, if properly inflated. If you have any indication a tire is not properly inflated, check the tire with a
                                                                  tire gauge. Also check for tread depth: A minimum
   Figure E-6. ABNORMAL TIRE WEAR PATTERNS                        depth of 4./32” is required on the front tires and
                                                                  2/32” on the rear tires as per Section 171.36 of
         SMOOTH          SMOOTH          CHEWED                   Title 67. The valve stem and cap should be in
                                                                  place and undamaged. Also, there should be no
                                                                  obstructions between the dual wheels.

                                                                Develop the habit of observing tires for abnormal
                                                                wear patterns, which may be a symptom of
                                                                suspension problems. Figure E-6 shows several
                                                                types of abnormal wear that can cause steering
                                                                problems, shimmy conditions and premature tire
                                                                wear. Do not operate the bus, if the tire has such
                                                                defects as bubbles, cracks or significant
                                                                abnormal tire wear patterns.


            OVER          UNDER    OUT OF
          INFLATED      INFLATED ALIGNMENT




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                                                                                 UNIT E - Preventative Maintenance



Check Right Front

  • Right fender-mounted mirror (previously outlined in this unit);
  • Right front tires, wheels and rims (previously outlined in this unit);
        v Condition,
        v Hub oil level adequate,
        v 4./32” tread depth.
  • Right front suspension;
        v Spring, spring hangers, shackles, U-bolts: Mount should be secure, not broken or cracked, without
          missing or loose bolts. Bushings and axle mounting parts should not be damaged, broken, or missing.
          Check for missing or broken leaves; leaves that have shifted and may be nearly in contact with the tire,
          rim, brake drum, frame, or body. For a coil spring, look for breaks or distortions.
        v Shock absorbers should be secure, unbroken and have no leaks.
        v A key with this inspection is to give valid information on important parts, and to know what constitutes
          an unsafe condition. YOU are responsible for safety.


                                          Figure E-7. Suspension System




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UNIT E - Preventative Maintenance



  • Crossing arm control should be secure and not broken;
  • Right front brake;
  	 v Brake drum – The brake drum should have no cracks, dents or holes, and no missing or loose bolts.
      Brake linings should not be worn thin.
  	 v	 Condition of hoses – Hoses should not be cracked, worn, or frayed, and couplings should be secure.
  	 v Slack adjuster (for air brakes) – The slack adjuster should have no broken, loose or missing parts.
      The angle between the push rod and the adjuster arm should be about 90 degrees when the parking
      brake is applied. When pulled by hand, brake push rod should move no more than about 1” (front
      brake).
  	 v Brake chamber (for air brakes).
  	 v	 NOTE: Valves and brake shoes cannot be checked by the operator during the pre-trip inspection.


Check Front Side
  • Condition of front axle;
  • Condition of steering system (See Figure E-8);
  	 v No loose, worn, bent, damaged, or missing parts.
  	 v Grab the steering wheel to test for looseness. Steering wheel play should not be more than 10 degrees
      or two inches of movement at the rim of a 20-inch diameter steering wheel.
  	 v Steering box and steering linkage: Look for missing nuts, bolts, fluid leaks, and damage to the power
      steering hose. No connections to the front wheels should be cracked.
                                                                      •   Condition of windshield;
                  Figure E-8. Steering System
  	 	                                                                 	   v   Check for damage.
  	 	                                                                 	   v	 Clean it if dirty. Never wipe a
                                                                             dry window or mirror; this can
                                                                             cause fine scratches. When
                                                                             cleaning the windshield,
                                                                             never move the wiper arms
                                                                             from side to side because
                                                                             this breaks the gear in the
                                                                             motor. You can lift the wiper
                                                                             straight off of the windshield
                                                                             and then drop it back into
                                                                             place after cleaning.
  	 	                                                                 	   v   Check the windshield wiper arms
                                                                              for proper spring tension.
  	 	                                                                 	   v   Check wiper blades for damage,
                                                                              “stiff” rubber, and secure
                                                                              attachment.
                                                                      •   Lights and reflectors;
  	 v	 Parking, clearance and identification lights are clean, operating and proper color (amber at front).
  	 v Reflectors are clean and proper color (amber at front).
    v Front turn signal light is clean, operating and proper color (amber or white on signals facing forward).
  	 v Left school bus eight-way light system – is clean and operating.



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                                                                                 UNIT E - Preventative Maintenance



  Check Left Front
  • Check all items as for right front;
  • Check left side stop arm and wing guard. The Stop sign should come out with the lights and indicators
    flashing alternately; and
  • Check left front fender rear and crossover mirrors as the right front.


  Check Left Side
  • Left fuel tank(s);
       v Securely mounted, not damaged or leaking,
       v Cap(s) on and secure.
  • Battery check;
       v Securely mounted,
       v Adequate fluid level,
       v No leaks.
  • Condition of visible parts;
       v Transmission not leaking,
       v Exhaust system is secure, not leaking, not touching wires, fuel, or air lines,
       v Frame and cross members have no bends or cracks,
       v Air lines and electrical wiring are secured against snagging, rubbing and wearing;
       v Spare tire carrier or rack is not damaged (if equipped),
       v Spare tire and/or wheel is securely mounted in rack, and
       v Spare tire and wheel adequate (proper size, properly inflated).


  Check Left Rear
  • Check left rear tires, wheels and rims (previously outlined in this unit);
  	 v General condition,
       v Hub oil level adequate,
       v 2/32” tread depth,
       v Make sure there are no obstructions between the dual wheels.
  • Suspension: Same as front right suspension (previously outlined in this unit);
       v Condition of spring, spring hangers, shackles, U-bolts,
       v Axle is secure.
  • Brakes – Same as front right suspension (previously outlined in this unit);
       v Condition of brake drum(s),
       v Condition of hoses,
       v Slack adjuster (for air brakes),
       v Brake chamber (for air brakes).
  • Lights and Reflectors;
  	 v Side-marker lights are clean, operating and proper color (red at rear, others amber),
       v Side-marker reflectors are clean and proper color (red at rear, others amber),


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UNIT E - Preventative Maintenance



  Check Rear Side
  • Lights and Reflectors;
  	 v Rear clearance and identification lights are clean, operating and proper color (red at rear),
  	 v Reflectors are clean and proper color (red at rear),
  	 v Tail lights are clean, operating and proper color (red at rear),
  	 v Rear turn signal is operating and proper color (white, red or amber at rear).
  • License plate(s)is present, clean and secured;
  • Splash guards are present, not damaged, properly fastened, not dragging on ground or rubbing tires;
  • Rear emergency door and side emergency door exits open and close properly from outside the bus;
  • Exhaust system;
  	 v Pipes, muffler, tailpipe and hangers are securely mounted without cracks, holes, or severe dents,
  	 v Muffler and pipes should not be touching wires, fuel hoses or air hoses,
  	 v No excessive smoke, hissing, vibration, or noise,
  	 v The tailpipe does not extend beyond two inches from the rear of the vehicle.


  Check Right Rear
  • Check all items as on left side and fuel tank area including straps, cap, and signs of fuel leaks:


5.      CHECK BRAKE SYSTEM
Brakes are the most critical piece of safety equipment on your vehicle. You will need to make sure they are
working properly before taking your bus on the road. This includes the parking brake and the service brake.

  To test the parking brake:
     1. Fasten seat belt;
     2. Allow bus to move slowly forward; and
     3. Apply parking brake. If the bus doesn’t stop, it’s faulty, and you must get it fixed before taking your bus
        on the road.


  If your bus is equipped with hydraulic brakes, test for hydraulic leaks:
     1. Pump the brake pedal three times;
     2. Apply firm pressure to the pedal and hold for five seconds; and
     3. The pedal should not move. If it does, there may be a leak or other problem. Get it fixed before
        operating the vehicle.


If your bus is equipped with air brakes, refer to Sections 5. and 10 of the Commercial Driver’s License Manual
for testing. The manual is available on PennDOT’s Driver and Vehicle Services website, www.dmv.state.pa.us
under the Commercial Driver Information Center.




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                                                                                 UNIT E - Preventative Maintenance



Here are some procedures for an air brake test:
  • With the engine running, build the air pressure to the governed cut out (typically 100-125. psi) and shut off
    the engine. Turn the key, but do not start the engine; chock your wheels and release the parking brake.
    Check the air gauge to see if the pressure drops more than two psi in one minute. If the air loss is greater,
    check for leaks and fix before driving.
  • Then fully apply pressure to the foot brake and hold for one minute. Check the air gauge to see if the
    pressure drops more than three psi. If the air loss is greater, check for leaks and fix before driving.
  • Begin fanning off the air pressure by rapidly applying and releasing the foot brake. The low air warning
    devices (buzzer, light, flag) should activate before the pressure drops below 60 psi.
  • Continue to fan off the air pressure. At approximately 4.0 psi to 20 psi, the parking brake valve should close
    by popping out.
  • Check the air pressure build-up rate by starting the engine. When the engine is at operating RPM, the
    pressure should build from 85. to 100 psi within 4.5. seconds in dual air systems. If the vehicle has larger
    than minimum air tanks, the build-up time can be longer and still be safe. Check the manufacturer’s
    specifications.



Regardless of what type of brake system your school bus is equipped with:
   1. Release the parking brake;
    2. Move forward at about five MPH;
    3. Push brake pedal firmly; and
    4.. Watch for “pulling” to one side or any unusual brake pedal “feel” or delayed stopping action. These may
        indicate trouble, and you should have the bus serviced.



Automatic Slack Adjusters (ASAs)
All airbrake vehicles manufactured since Oct. 20, 1994., are required to have automatic slack adjusters (ASAs).
ASAs should not have to be manually adjusted except when performing maintenance on the brakes and during
the installation of the brake adjusters. In a vehicle equipped with ASAs, when the pushrod stroke exceeds the
legal brake adjustment limit, it is an indication a mechanical problem exists in the adjuster itself, a problem with
the related foundation brake components or the adjuster was improperly installed.

The manual adjustment of an ASA to bring a brake pushrod stroke within legal limits is generally masking a
mechanical problem and is not fixing it. Further, routine adjustment of most ASAs will likely result in premature
wear of the adjuster itself. It is recommended when brakes equipped with ASAs are found to be out of
adjustment, you take the vehicle to a repair facility as soon as possible to have the problem corrected. The
manual adjustment of an ASA should only be used as a temporary measure to correct the adjustment in an
emergency situation, as it is likely the brake will soon be back out of adjustment since this procedure usually
does not fix the underlying adjustment problem. ASAs are made by different manufacturers and do not all
operate the same. Therefore, the manufacturer’s service manual for the specific ASA being used should be
consulted prior to troubleshooting a brake adjustment problem.)

Once everything has been completed, check for all required papers, trip manifests, permits, etc., and secure all
loose articles in driver’s compartment.




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      PREVENTIVE MAINTENANCE WHILE ON THE ROAD
The previous section detailed checks you should make before leaving on your daily route. This section deals
with preventive maintenance while on the road. The section is divided into two parts: detecting abnormal
vehicle behavior, and following good driving habits that will extend the life of the vehicle and its components.




            DETECTING ABNORMAL VEHICLE BEHAVIOR
Detecting abnormal vehicle behavior requires you to use most of your senses: sight, sound, smell, and touch.
As a first step, you must learn to recognize the normal running condition of the vehicle while at the wheel so
you can compare normal conditions with unusual steering, rattles, odd smells, or other conditions. For this
reason, and as a vital safety practice, it is important to road test the vehicle every morning before picking up
the first passenger. This is not to say that after the road test, your preventive maintenance responsibilities are
over. Throughout a trip, you should constantly monitor the engine gauges and the general operating condition
of the vehicle in the same manner as during the road test.

Continuous Checks
  • Watch gauges and instruments for trouble:
    v Instruments;
    v Air pressure gauge (if you have air brakes);
    v Temperature gauges;
    v Pressure gauges;
    v Ammeter/voltmeter;
    v Use your senses (sight, sound, smell, feel) to check for problems.
  • Check critical items when you stop:
  	 v Tires, wheels, and rims;
  	 v Brakes;
    v Lights.
  • Watch your mirrors.
  • If you see, hear, smell, or feel anything that might mean trouble, check it out.


Check Parking Brake
Check the parking brake again before pulling out onto the road.

  • If your bus is equipped with a ratchet-type lever, you should feel a distinct clicking of the ratchet pawl and
    the lever should lock firmly into place when you apply the brake. When properly adjusted, this brake
    should be capable of holding the bus on a hill. If you detect excessive looseness or lever travel, the lever
    slipping out of locked position, the lever binding, or the brake not holding the bus on a hill, have the
    parking brake adjusted.
  • If the parking brake is an over-center type, it should not take excessive effort to apply, but it should still
    prevent the vehicle from rolling on a grade or with the transmission in gear.
  • If the bus is equipped with air brakes, pull out the parking brake control knob to engage the parking brake.
    Put the bus in low gear and pull against the parking brake. If the vehicle does not hold with the parking
    brake knob in the engaged position, have the rear brakes adjusted.




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                                                                                 UNIT E - Preventative Maintenance



Check Service Brakes
Check the service brakes after the parking brake, preferably before reaching the highway. Test at low speeds
by bringing the bus smoothly to a complete stop. Your bus should stop in a straight line without skidding,
swerving, pulling to either side, grabbing, locking, or making excessive noise.

  • For buses with hydraulic brakes, the brakes should not need to be pumped to have braking power and
    should not need excessive pedal effort to engage. If they need either, have the brakes adjusted.
  • With air brakes, the bus should stop as described above, but you have an additional check. Since air
    pressure is being used to apply the brakes, you will see some loss of pressure (as indicated on the air
    pressure gauge). In general, a brake adjustment is required, if the gauge pressure drops by more than 10
    lbs. during a single brake application.
  • Check the air pressure gauge, and vacuum the gauge periodically while on the road.


Check Transmission
Automatic transmissions should not slip or produce harsh, jerking shifts. With a manual transmission, ensure all
forward and reverse gears engage smoothly with no unusual metallic clashing noises, burning clutch smells or
shifting difficulties. The clutch should engage easily and smoothly, without jerking, slipping excessively, or
chattering. Also, with a properly adjusted clutch, the pedal should move freely for approximately the first 1 to
1½ inches. Greater or lesser amounts of free clutch travel, or freeplay as it is commonly called, may indicate
clutch wear.


Check Steering
While the bus is moving straight ahead, check the steering for the amount of play or looseness in the wheel.
Check for a binding feel or any unusual noises when making full turns. As with the other checks above, report
any unusual conditions at once.


Check Suspension
To ensure safe control of the bus while on the road, check the suspension. The suspension may have a
malfunction, if the bus sags at one end or corner or if it bounces excessively. Also check that the bus tracks
properly and does not weave or sway when turning.


Check Engine
In addition to periodic gauge checks, especially oil pressure, temperature and ammeter/ voltmeter, listen for
any unusual engine noises. Note any hesitation in acceleration or any power loss when going uphill. This
behavior can indicate cylinder misfires, damaged valves, a restricted exhaust system, or inaccurate engine
timing. All of these problems can cause early engine wear and excessive fuel consumption.

As stated earlier in this section, you should continually check the items mentioned above while on the road.
However, it is especially important to make these checks before picking up your first passenger. Report any
abnormal operating condition immediately.


Check Your Tires
As mentioned in the pre-trip inspection, pay particular attention to your tires: proper inflation, no unusual wear,
and proper tread depth, 4./32” on front tires and 2/32” on rear tires.




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UNIT E - Preventative Maintenance



GOOD DRIVING HABITS
The second part of your on-the-road preventive maintenance responsibility is operating the vehicle properly
through good driving habits. Most of the procedures to be covered in this section will have no immediate effect
on the vehicle’s operation, but if practiced regularly, they will significantly increase the lifespan of the vehicle
components.


Starting the Bus and Basic Operations
When starting your bus, don’t engage the starter for more than 10 seconds. This could cause damage to the
flywheel or other parts. Never operate a bus with an overheated engine or with low oil pressure. This can cause
serious engine damage – pay attention to your gauges.

To ensure proper service length for tires and to avoid damage while driving, never operate your bus with flat or
under-inflated tires. Driving over curbs, objects and into potholes can damage tires quickly as can rubbing tires
against curbs.

Don’t idle excessively. A diesel bus gets warm by driving it. You won’t get heat until the bus is operating on the
road. It will not get warm sitting and idling no matter how long you let it idle.


Proper Use of the Clutch
The clutch is the most abused component in the bus because of frequent use and because many drivers do not
understand its function. A clutch assembly will give many miles of trouble-free operation, if you drive properly
and maintain the clutch properly.

Here are some pointers:
  • Don’t use the clutch as a brake. Many drivers incorrectly use the clutch as a brake. For example, they will
    stop on an incline and, by feathering the clutch (letting the clutch partially out), hold the bus from rolling.
    By so doing, they force the slipping clutch to hold the entire weight of the bus and passengers. This severe
    friction generates excessive heat, which greatly shortens the life of the clutch.
  • Don’t ride the clutch. The throw-out bearing is a component of the clutch that does not turn when the
    clutch pedal is released, its normal position during driving. “Riding the clutch” is when the weight of a
    driver’s foot resting on the clutch pedal is enough to move the throw-out bearing forward until it makes
    contact with the pressure plate and spins at the same speed as the engine. This serves no purpose except
    to increase wear and cause premature destruction of the bearing. The bearing is engineered to last a
    certain length of time and is factory packed in enough grease for this usage. Excessive use will use up
    this grease and will burn out the bearing. When shifting, use the clutch briefly and smoothly to achieve
    maximum durability.
  • Make sure the clutch is adjusted properly. Another term you may have heard is toeboard clearance or
    freeplay. This refers to the amount of travel of the clutch pedal between its highest position and the point
    where you can feel contact being made. This clearance must be maintained in order to prevent the
    throw-out bearing from turning. On most equipment, clearance should be approximately 1 to 1½ inches.
    Due to normal wear of the clutch, clearance decreases gradually. The clutch should be adjusted frequently
    to maintain freeplay. Alert your supervisor or mechanic, if the clutch needs to be adjusted.




Pennsylvania School Bus Driver’s Manual • PUB 117                                                              E-21
                                                                              UNIT E - Preventative Maintenance



Proper Use of the Brakes
Brakes are another commonly abused vehicle component. You can extend brake life if you follow a few
pointers. By watching the traffic ahead, you can observe when you may have to stop; slow the bus by letting up
on the gas pedal prior to the stop so the brakes will be used lightly and only for a short time. You can use the
engine’s braking power to slow the bus prior to making a stop and to control your speed on downgrades. When
stopping, apply the brakes gently whenever possible and ease up on pedal pressure as speed drops so you
are using very light pressure at the end of the stop. Do not:

    •   Disengage the clutch until the bus has almost stopped; and
    •   Brake quickly or harshly or for extended periods of time on downgrades.
Both of these actions cause excessive brake heat and shorten brake life and braking effectiveness. Delayed
braking can result in abrupt stops and ultimately in crashes. For buses with automatic transmissions, refer to
the section on shifting procedures in Unit F (Driving Fundamentals).


Protection of the Rear Axle
Protection of the rear axle is a third good driving habit. For long rear axle life, never spin the rear wheels on
slippery surfaces (such as snow or ice) or loose surfaces (such as sand or gravel). If the rear wheels spin for a
long time, the high speed will throw the lubricant out from between the gears, which can damage the differential
assembly. In more extreme cases, the internal gears may seize and break the shaft. Also, if a spinning wheel
suddenly hits dry pavement or solid ground, the resultant shock can totally destroy the differential.


Proper Use of the Transmission
Proper use of the transmission can save wear and tear on gears, clutch, engine, and brakes. Maintain a
constant speed whenever possible to save fuel and reduce wear on drive line components.


Manual Transmission.
With a manual transmission, always start the vehicle moving in low gear, moving at a slow rate of speed. This
will ensure proper lubrication of internal transmission and rear axle parts, and will avoid the possibility of
lugging the engine or slipping the clutch. As you move faster, progressively shift the transmission to the gear
that will maintain the desired road speed. When driving a vehicle with a manual transmission:

  • Always start off in first gear when carrying a heavy load;
  • With a four-speed transmission, use first through fourth gears on level ground;
  • With a five-speed transmission under light load conditions, use second through fifth gears for normal
    driving;
  • When going up hills, downshift to avoid lugging the engine;
  • When going down a hill, use one gear lower than would be required to go up the hill. Using lower gears
    will help slow the bus down and prevent the brakes from overheating due to excessive use; and
  • Stop completely before shifting into first gear or reverse.




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UNIT E - Preventative Maintenance



Automatic Transmission.
For vehicles equipped with automatic transmissions, proper selection of the correct gear provides better control
without undue wear on the transmission. Avoid using the accelerator to hold a vehicle with an automatic
transmission on a hill. When driving a vehicle with an automatic transmission, use the gearshift as described in
the owner’s manual for better vehicle control. Shifts are especially helpful when approaching hills and grades.
Before driving a bus equipped with an automatic transmission for the first time, consult the owner’s manual for
detailed operating instructions. While the preventive maintenance on-the-road checks and driving habits
presented in this section are vitally important to the safe operation and long life of the vehicle, your single most
important preventive maintenance responsibility is to immediately and accurately report any malfunctions.




 POST-TRIP PREVENTIVE MAINTENANCE PROCEDURES
Your maintenance responsibilities are not over until you stop the vehicle, check it over, and report its condition
to your supervisor or maintenance department. Complete the following steps at the end of every trip:

  • If possible, fill the fuel tank in the evening rather than waiting until the following morning, if this is one of
    your responsibilities. This will reduce the overnight condensation of water vapor inside the fuel tank.
  • When parking your bus, after you set the parking brake and put the transmission in neutral, allow the
    engine to idle slowly as per manufacturer’s recommendations. This will permit proper lubrication of all
    engine parts, and is of particular importance for diesel vehicles.
  • While the engine is idling, check the interior for broken windows, ripped seats or other damage that should
    be repaired before the bus is used again. Check on and under the seats for sleeping students, books,
    clothes or other materials that may have been left by the students.
  • Sweep the floor and steps of the bus. Enforcing a clean bus policy with your students will help you
    maintain your bus. Also, periodically washing the interior of the bus including seats, windows and
    windowsills is good practice.
  • Check the exterior of the bus for burned out bulbs or other damage that needs to be repaired. Re-enter
    the bus, turn off all electrical equipment, shut off the engine, remove the keys, and secure the bus.
  • Generally, drivers should remove the key from the ignition. Check with your supervisor for your local policy
    on this issue.



Remember that federal regulations in 4.9 CFR Section 396.11 require every motor carrier require its drivers to
report, and every driver shall prepare a report in writing at the completion of each day’s work on each vehicle
operated, and the report shall cover at least the following parts and accessories:

  • Service brakes, including trailer brake connections;
  • Parking (hand) brake;
  • Steering mechanism;
  • Lighting devices and reflectors;
  • Tires;
  • Horn;
  • Windshield wipers;
  • Rear vision mirrors;




Pennsylvania School Bus Driver’s Manual • PUB 117                                                                  E-23
                                                                                  UNIT E - Preventative Maintenance



   • Coupling devices;
   • Wheels and rims; and
   • Emergency equipment.
The regulation also details report contents, corrective actions and exceptions.



IMPORTANCE OF REPORTING PROBLEMS
Clearly, your responsibilities as a school bus operator include reporting any and all abnormal conditions
encountered during the day to your supervisor or maintenance department. This could be something you
discovered in the pre-trip inspection, while the bus was in service, or after your trip. Failure to inspect
equipment before each trip and failure to report defects and needed repairs cannot only create costly
maintenance problems, it can also create an unsafe condition for you and your passengers. Remember,
problems cannot be repaired, if they are not reported.

When reporting, be accurate in describing the problem; you do not needed to diagnose. Mechanics will need
accurate information on:

    1. Location;
    2. Timing;
    3. Sounds; and
    4.. Other descriptive characteristics.
Write it down, pass it on, get it fixed.

Report anything affecting safety or possibly leading to mechanical breakdown. The vehicle inspection report
tells the vehicle owner about problems that may need to be fixed. Keep a copy of your report in the vehicle for
one day. That way, the next driver can learn about any problems you have found. Federal regulations outline
additional recordkeeping requirements and timeframes. Refer to 4.9 CFR Sections 396.3 and 396.21.



FIVE BASIC ITEMS MECHANICS WANT YOU TO KNOW
    1. Understand and learn to read your gauges. Knowing your voltage meter, oil pressure and water
       temperature readings could save your engine.
    2. When you first notice any type of repair that needs to be done, write it up immediately. This could
       prevent a major repair later and be less costly to fix.
    3. If you drive a diesel bus, remember to let your bus idle as per manufacturer’s recommendations in the
       lot before you turn it off. This will cool down the turbocharger and may extend engine life.
    4.. If you have a flat tire in a rear wheel, do not drive on it. A minor cost can turn into an expensive
        replacement.
    5.. The glow plug (if equipped with one) on the dash on a diesel bus will go out when the bus is ready to
        start.




E-24.                                                          Pennsylvania School Bus Driver’s Manual • PUB 117

				
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